title: Serum levels of glycoprotein Dickkopf-1 in patients with cutaneous malignant melanoma: a prospective pilot study.
abstract: BACKGROUND
  Dickkopf-1 (Dkk-1) glycoprotein is an inhibitor of the canonical Wnt pathway. Recent studies have demonstrated elevated Dkk-1 serum levels in patients with diverse malignancies. In vitro studies with melanoma cell lines showed that loss of Dkk-1 expression may contribute to tumor progression.
  
  
  OBJECTIVE
  The present study is the first in vivo investigation of Dkk-1 serum levels in patients with cutaneous malignant melanoma.
  
  
  METHODS
  We analyzed serum levels of Dkk-1 protein in 82 patients with cutaneous melanoma.
  
  
  RESULTS
  Serum levels were significantly increased (mean 83.01 pmol/l) in comparison to healthy controls (mean 29.36 pmol/l). No statistical difference in Dkk-1 serum levels neither between patients without or with lymph node metastases (p = 0.719) nor between patients with or without visceral metastases (p = 0.929) was found. Patients before excision had moderately higher Dkk-1 serum levels than after excision or with florid metastases.
  
  
  CONCLUSIONS
  Our data suggest that increased Dkk-1 expression is an early event in melanoma, decreasing in later tumor stages. It was shown previously that Dkk-1 activates cell death in melanoma cells. Our in vivo data indicate that a decrease in Dkk-1 could be a sign of loss of tumor control.
authors.affiliation: Department of Dermatology, Hietzing Municipal Hospital, Vienna, Austria. robert.feldmann@wienkav.at
authors.forename: Robert
authors.initials: R
authors.lastname: Feldmann
authors.forename: Michael
authors.initials: M
authors.lastname: Schierl
authors.forename: Astrid M
authors.initials: AM
authors.lastname: Fink
authors.forename: Paul-Gunther
authors.initials: PG
authors.lastname: Sator
authors.forename: Jacob
authors.initials: J
authors.lastname: Maiweg
authors.forename: Andreas
authors.initials: A
authors.lastname: Steiner
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D005260:Female; D006801:Humans; D036341:Intercellular Signaling Peptides and Proteins / Q000097:blood*; D008207:Lymphatic Metastasis; D008297:Male; D008545:Melanoma / Q000097:blood* / Q000473:pathology; D008875:Middle Aged; D010865:Pilot Projects; D011446:Prospective Studies; D012878:Skin Neoplasms / Q000097:blood* / Q000473:pathology; D055815:Young Adult
chemical_list: C501126:DKK1 protein, human; D036341:Intercellular Signaling Peptides and Proteins